Teen sexually assaulted by four men at party

A 20-year-old man will remain in custody after he allegedly sexually assaulted a teenage girl with three other men at a party in Sydney's west.

Valentino Hrdavec faced Blacktown Local Court today charged with the aggravated sexual assault of an 18-year-old nearly two weeks ago.

Police say Hrdavec and three other men, aged between 19 and 27, sexually assaulted the teenager at a June 21 party at a home in Blacktown.

The teenager told her mum about the alleged assault, who then called police.

The four men will face Blacktown and Penrith courts in coming months.